DEMARTIN Electropolishing

DEMARTIN Electropolishing

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Electropolishing, also known as electrolytic polishing or electropolishing, is an innovative electrochemical process for the surface treatment of metals, especially stainless steels. In this process, the workpiece is placed as an anode in an electrolyte specially adapted to the material. The controlled current flow selectively removes metal ions from the surface, levelling unevenness and roughness in the micro range.

In contrast to mechanical polishing processes, electropolishing removes material without subjecting the workpiece to thermal or mechanical stress. This effectively eliminates microcracks, structural defects and localised stresses in the surface layer, which leads to an improvement in the material properties. In addition, the increased removal on edges and corners results in ultra-fine deburring and smoothing of the surface.

The result of electropolishing is a metallically pure, shiny and micro-smooth surface with optimised properties of the base material. The electropolished surfaces are characterised by increased corrosion resistance, improved cleanability and reduced microbial adhesion. Friction is also reduced, which leads to increased wear resistance in mechanically stressed parts.

Electropolishing is used in a wide range of industries, including medical technology, the food and pharmaceutical industries, pipeline and container construction and aerospace technology. The process is also used for decorative purposes, such as for façade panels and jewellery.

The process control for electropolishing requires careful adjustment of the parameters, such as current density, electrolyte composition and treatment duration, to the respective workpiece and material. Thorough pre-cleaning of the surfaces is also crucial for an optimum result. Precise control of the process conditions enables reproducible results to be achieved within narrow tolerances.

All in all, electropolishing is a powerful process that offers an efficient and economical solution for the treatment of metal surfaces by combining surface finishing, cleaning and deburring in a single work step. With its versatility and outstanding results, electropolishing has established itself as an indispensable technology in modern surface technology.


Advantages

  • Increased corrosion resistance by removing surface impurities and improving the passive layer
  • Improved surface smoothness and reduction of micro-roughness
  • Creation of a metallically pure, shiny and decorative surface
  • Removal of burrs, edges and surface defects such as cracks
  • Reduced friction and increased wear resistance
  • Improved cleanability and reduced adhesion of impurities
  • Increased fatigue strength through reduction of surface stresses
  • Visualisation of material defects and microstructures for quality control
  • Applicability to complex geometries and hard-to-reach areas
  • Uniform treatment without mechanical or thermal stress on the workpiece
  • High reproducibility and control of the process
  • Wide range of applications for various metals and alloys

Specifications

Electrochemical
Passivation
no application
Removal
usually 3-5 um

Applications

  • Medical technology:
    • Surgical instruments such as scalpels, clamps, saws
    • Medical implants and prostheses
    • Medical devices such as ventilators and rehabilitation equipment
    • Manufacturing of Covid vaccines
  • Food and beverage industry:
    • Processing equipment such as kettles, vats, containers
    • Packaging machinery and conveyors
    • Cookware, pans, wire racks
    • Utensils and cutlery
  • Pharmaceutical industry:
    • Production facilities and equipment
    • Piping, valves, containers
    • Cleanroom components
  • Aerospace:
    • Engine components and landing gear
    • Hydraulic systems and fuel lines
    • Precision components for avionics and flight instruments
  • Semiconductor industry:
    • Clean room equipment and furniture
    • Precision components for chip production
    • Wafer carriers and holders
  • Automotive industry:
    • Fuel lines, injectors, valves
    • Transmission parts and engine components
    • Exhaust systems and exhaust pipes
    • Rims, trims, grills
  • Oil and gas industry:
    • Piping, valves, pumps
    • Heat exchangers and reaction vessels
    • Storage tanks and mixing vessels
  • Energy generation:
    • Solar panels and semiconductor components
    • Nuclear reactor components
    • Heat exchangers and pipework
  • Textile and paper industry:
    • Guide rollers, deflection rollers, cutting knives
    • Spinning and weaving machines
    • Punching tools and cutting devices
  • Decorative applications:
    • Sanitary fittings and accessories
    • Art objects and sculptures